Novak Djokovic backlash 'all part of being Boris Becker'

Novak Djokovic won his first grand slam title since hiring Boris Becker as coach at Wimbledon in July 2014. The pair have been working together since December 2013.

Becker (right) in conversation with Djokovic at the 2014 Australian Open in Melbourne, where he lost in the quarterfinals. The 46-year-old German is one of several former grand slam champions to recently take up a coaching role with a top player.

Becker won six grand slam titles during a 15-year career. Since retiring in 1999 he has become a skilled summarizer for broadcasters around the world. His decision to switch to coaching surprised everyone, not least because he has never done it professionally before.

However, the pairing of 17-time grand slam champion Roger Federer and Stefan Edberg seemed obvious. The Swede, a six-time grand slam winner himself, was a player Federer idolized when he was growing up. Both men are renowned for being extremely stylish players.

"He's such a great player, but there's always minor things you can work on," Edberg said. "I really think I can make a little difference. And if I can, maybe that will take him back to where he was."

Eight-time grand slam champion Ivan Lendl helped Andy Murray to win his first two major titles, as well as an Olympic gold medal.

Since splitting with Lendl in March 2014, Murray has teamed up with former women's No. 1 Amelie Mauresmo.

Former Wimbledon champion Goran Ivanisevic is something of a veteran on the coaching circuit compared to the likes of Becker and Edberg, having started coaching fellow Croatian Marin Cilic in 2010.

Michael Chang (right), who stunned Edberg in the 1989 French Open final as a teenager, took up a coaching role with rising Japanese star Kei Nishikori last December.

Spain's two-time French Open winner Sergi Bruguera started coaching France's Richard Gasquet in February 2014.

(CNN) -- It wasn't often Boris Becker was caught out by a barrage of volleys on the court -- but the tennis great says he was stunned by the level of criticism he received after being appointed as Novak Djokovic's coach.

Eyebrows were raised when Becker, a six-time grand slam winner, swapped his seat in the television commentary box to take up a role with the Serbian star in December 2013.

Becker, who won 64 ATP titles and three Wimbledon crowns during a stellar 15-year career, is one of the most popular faces in the sport.

But he says the level of negative attention the move attracted from both inside and outside of the game was "all part of being Boris Becker."

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"It was a little bit strange and I was a little bit surprised," the German told CNN's Open Court ahead of the U.S. Open starting on Monday.

"I wasn't aware I had that many doubters. I must have stepped on many toes in my life for all of them to beat the bushes and raise their opinion.

"We live in a free world and everyone is entitled to their own opinion, but I was a little bit surprised."

Becker, who ended his playing days in 1999, had never coached a top player on tour before joining forces with Djokovic.

"I like to think that I'm very comfortable within the tennis community so I was surprised by some of the doubters, but this is sometimes a part of being Boris Becker," the 46-year-old said.

"You're in the front row of life and in the headlines all the time, so a lot of people feel they're entitled to their opinion, even though they don't know anything about me."

Becker took on the challenge of restoring Djokovic to the top of the game, having lost his edge in the big matches.

He had started 2013 in confident mood by winning a third consecutive Australian Open, but the rest of the year was disappointing, losing to Rafael Nadal in the semis of the French Open and the final of the U.S. Open either side of defeat in the Wimbledon final against Andy Murray.

Becker was introduced to the Djokovic camp ahead of the 2014 Australian Open but could only watch from the sidelines as his man relinquished his grip on the title at Melbourne Park, losing to eventual champion Stan Wawrinka 9-7 in the fifth set of their quarterfinal clash.

That setback brought about fresh criticism of Djokovic's relationship with Becker -- though the German says that defeat provided the springboard which culminated in the 27-year-old winning his second Wimbledon title in July and reclaiming the No. 1 ranking.

A five-set victory over Roger Federer gave Djokovic a seventh grand slam and went a long way to vindicating Becker's decision.